1. Technical Field
The present invention relates to the recognition of a track of a moving object, and more particularly to a method for moving object detection and a hand gesture control method based on the moving object detection.
2. Related Art
One developing trend among computer devices has been to input instructions by hand gestures instead of directly contacting a computer device. In a conventional gesture input system, a user has to wear special gloves or finger cots, which are used for sensing a change of a posture or position of palms, so as to generate a corresponding input instruction. In view of the inconvenience caused by using the gloves or finger cots, the gesture image recognition technology has been introduced into a hand gesture control system, in which a video camera is used to capture hand gesture images and analyzes a change of a posture or position thereof, so as to generate a corresponding input instruction.
The current hand gesture recognition technology recognizes a change of a posture or position of a palm by using preprocessed hand contour images. For example, as disclosed in Taiwan Patent No. 393629 and I224288, different algorithm mechanisms are used to convert images and a palm is found out from each image by specific features as hand gestures. Taiwan Patent No. I298461 has illustrated discovering a static hand gesture image from images and then comparing the static hand gesture image with a specific gesture image in a database. The successful recognition in the above methods all depends on the factor whether a gesture contour can be accurately cut or line features of the gesture contour can be precisely extracted from the images. However, the process of cutting the gesture contour and extracting the line features is usually influenced by factors such as background, light source, and shadow. Meanwhile, the distance between a hand and a video camera and the posture change of the hand or the palm itself further influence the process of cutting the gesture contour. In order to improve the recognition rate, a database with a large number of preset gestures has to be created for making comparison, or an error tolerance is increased. In one aspect, when the database with a large number of preset gestures is used for making comparison in the recognition, the recognition speed is influenced and more hardware resources has to be consumed. In another aspect, the increase of the error tolerance further increases a probability of incorrect recognition results.
In the above patents as the prior art, the recognition is performed on a static hand image, so that the process of cutting a gesture contour, extracting line features, and making comparison with a database needs to be performed. In contrast, Taiwan Patent No. I274296 and U.S. Pat. No. 5,594,469 have disclosed to search for a dynamic object in successive images to recognize a dynamic gesture image. However, in Taiwan Patent No. I274296 and U.S. Pat. No. 5,594,469, an object other than the palm is easily regarded as a dynamic hand gesture, causing misjudgment under the influence of ambient light, movement of a human in the environment, face skin color, camera lens shaking, or image noise. Therefore, although the dynamic hand gesture recognition does not require cutting a gesture contour precisely, the problem of misinterpreting a moving object, noise, or the like as a dynamic hand gesture, still needs to be solved.